I. Field of the Invention
Disclosed is a composition for a soluble calcium-magnesium preparation, comprised of an effervescent preparation of calcium and magnesium with additional citric acid in a defined ratio. Besides making the product rapidly soluble, the citrate-rich composition ensures adequate increase in serum citrate to attenuate the rise in ionized calcium concentration to help prevent heart attacks. The composition also provides soluble calcium and magnesium to prevent osteoporosis-related fractures and low blood magnesium from the use of proton pump inhibitors (PPIs).
II. Description of the Related Art
Calcium supplements are widely used to supplement the diet to meet recommended dietary allowance and as a concomitant therapy with more specific anti-osteoporosis drugs. It has been traditionally believed that a calcium supplement should be soluble and bioavailable to effectively prevent osteoporosis.
However, a concern has been raised recently that calcium supplements might increase the risk of heart disease and heart attacks by producing a marginal rise in serum calcium (hypercalcemia). Thus, the more bioavailable a calcium supplement, the more likely it might be to cause this complication. Several epidemiological studies revealed an increased risk of heart attacks among subjects taking calcium supplements (Bolland, 2011; Reid, 2011; Li, 2012).
Similarly, magnesium is an important dietary component, touted for a variety of uses, such as avoiding magnesium deficiency, alleviating leg cramps and controlling constipation. Magnesium is also touted to have a beneficial effect on the muscle and heart (Kircelli, 2012). However, available preparations containing both calcium and magnesium are tablet formulations or emulsions with inadequate or poor solubility in water.
Common calcium and magnesium salts require gastric acid to be fully dissolved (Pak, 1989). When gastric acid secretion is blocked by proton pump inhibitors (PPIs), the resulting impairment in the solubility and absorbability of calcium and magnesium salts might increase the risk of osteoporosis-related fractures (Roux, 2009) and hypomagnesemia (Kuipers, 2009) that may cause muscle weakness, lethargy, abnormal heart rhythm, nausea and vomiting.
In conventional calcium supplements, the amount and form of calcium provided to avert bone loss may inappropriately raise serum calcium that might contribute to heart attacks. Furthermore, many conventional supplements of calcium and magnesium are poorly soluble during reduced gastric acid secretion of PPI use, leading to inefficient absorption of these substances. Thus, there remains a need for supplements that provide adequate calcium and magnesium in amounts and forms that are effective to achieve the benefits (prevention of bone loss during calcium supplements; avoidance of osteoporosis-related fractures and hypomagnesemia during PPI use) without adverse effects (heart attacks from calcium supplements).